Let's solve this addition problem. We have 2631 and 4268, and we need to add them together.

Step 1: We'll start by adding the digits 1 & 8 in column 1 and get 9.

Step 2: We'll start by adding the digits 3 & 6 in column 2 and get 9.

Step 3: We'll start by adding the digits 6 & 2 in column 3 and get 8.

Step 4: We'll start by adding the digits 2 & 4 in column 4 and get 6.

So, 2631 + 4268 = 6899.

